A metallized substrate for mounting semiconductor devices is formed to become an electronic component like light-emitting element by mounting, e.g., LD elements or LED elements on a substrate, and by sealing the upper portion of the substrate with a lid such as lens. At this circumstance, so as to secure long-term reliability and to protect embedded elements, it is necessary to completely shut off outside of the electronic component from inside of the same. Because of this, the metallized ceramics substrate is required to have high airtightness.
With developments in high integration of electronic components, wiring pattern and vias in the metallized substrate become miniaturized; so, electrical signals transmitted along wiring sometimes are delayed. Because of this, formation of low-resistant and highly-reliable wiring in a metallized substrate is demanded.
With respect to the technology of metallized substrate for mounting semiconductor device thereon, Patent document 1 discloses a plastic PGA-type package having a structure in which lead frame and copper foil are laminated so as to sandwich insulator, in which a cavity is formed to mount a semiconductor tip, and to which lead pins are inserted.
Patent document 2 discloses a ceramics PGA package fabricated by integrally firing a laminated body formed of a plurality of green sheets and the wiring patterns existing between the respective green sheets.
Patent document 3 discloses a laminated ceramics package which is formed by integrally laminating a plurality of ceramics layers, wherein metal layers are independently arranged to be electrically non-conductive, between ceramics layers being underneath a cavity. In addition, Patent document 4 discloses a multi-tip module including a multilayered wiring substrate on one surface of which is provided with electrode pads for connecting LSI tip and on another surface of which is provided with input terminals for connecting external circuit, a plurality of LSI tips, and a heat sink.
Patent Document 1: Japanese Patent Application Laid-Open (JP-A) No. 5-226513
Patent document 2: JP-A No. 6-53398
Patent document 3: JP-A No. 6-69567
Patent document 4: JP-A No. 6-77361